package Step1;
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */



import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

import UnionFind.UnionFindHashTable;

import BasicTypes.Constants;
import BasicTypes.Position;
import BasicTypes.Table;

/**
 * This is an example Hadoop Map/Reduce application.
 * It reads the text input files, breaks each line into words
 * and counts them. The output is a locally sorted list of words and the
 * count of how often they occurred.
 *
 * To run: bin/hadoop jar build/hadoop-examples.jar wordcount
 *            [-m <i>maps</i>] [-r <i>reduces</i>] <i>in-dir</i> <i>out-dir</i>
 */
public class Step1 extends Configured implements Tool {

  /**
   * Counts the words in each line.
   * For each line of input, break the line into words and emit them as
   * (<b>word</b>, <b>1</b>).
   */
	 public static void initJobConf(JobConf conf) {
		// Generating code using Karmasphere Protocol for Hadoop 0.18
		// CG_GLOBAL

		// CG_INPUT_HIDDEN
		conf.setInputFormat(org.apache.hadoop.mapred.KeyValueTextInputFormat.class);

		// CG_MAPPER_HIDDEN
		//conf.setMapperClass(Step1.Step1HadoopMapper.class);

		// CG_MAPPER
		conf.setMapOutputKeyClass(org.apache.hadoop.io.IntWritable.class);
		conf.setMapOutputValueClass(org.apache.hadoop.io.Text.class);

		// CG_PARTITIONER_HIDDEN
		conf.setPartitionerClass(org.apache.hadoop.mapred.lib.HashPartitioner.class);

		// CG_PARTITIONER

		// CG_COMPARATOR_HIDDEN
		conf.setOutputKeyComparatorClass(org.apache.hadoop.io.Text.Comparator.class);

		// CG_COMPARATOR

		// CG_COMBINER_HIDDEN

		// CG_REDUCER_HIDDEN
		//conf.setReducerClass(Step1.Step1HadoopReducer.class);

		// CG_REDUCER
		conf.setOutputKeyClass(org.apache.hadoop.io.IntWritable.class);
		conf.setOutputValueClass(org.apache.hadoop.io.IntWritable.class);

		// CG_OUTPUT_HIDDEN
		conf.setOutputFormat(org.apache.hadoop.mapred.TextOutputFormat.class);

		// CG_OUTPUT

		// Others
		}
	
	 public static class Step1HadoopMapper extends MapReduceBase implements Mapper<Text,Text,IntWritable,Text> {
		    // The Karmasphere Studio Workflow Log displays logging from Apache Commons Logging, for example:
		    // private static final Log LOG = LogFactory.getLog("Step1.Step1HadoopMapper");

			
			
		    @Override
		    public void map(Text key, Text value, OutputCollector<IntWritable, Text> output, Reporter reporter)
		            throws IOException {
		    	int k = Integer.parseInt(key.toString());
		    	int v = Integer.parseInt(value.toString());
		    	Position kP = new Position(k);
		    	//Position kV = new Position(v);
		    	int group = kP.x/Constants.COLUMESIZE;
		    	String str= key.toString() + " " + value.toString() + " ";
		    	output.collect(new IntWritable(group), new Text(str));
		    }
		}
  /**
   * A reducer class that just emits the sum of the input values.
   */
	 public static class Step1HadoopReducer extends MapReduceBase implements Reducer<IntWritable,Text,IntWritable,IntWritable> {
		    // The Karmasphere Studio Workflow Log displays logging from Apache Commons Logging, for example:
		    // private static final Log LOG = LogFactory.getLog("Step1.Step1HadoopReducer");

			@Override
		    public void reduce(IntWritable key, Iterator<Text> value, OutputCollector<IntWritable, IntWritable> output, Reporter reporter)
		            throws IOException {
		       int group = key.get();
		       UnionFindHashTable uf = new UnionFindHashTable();
		       //QuickUnion qu = new QuickUnion((Constants.COLUMESIZE + 1) * Constants.SIZE, group);
		       while (value.hasNext()) {
		    	StringTokenizer st = new StringTokenizer(value.next().toString());
				int p = Integer.parseInt(st.nextToken());
				int q = Integer.parseInt(st.nextToken());
				uf.unite(p, q);
		       }
		       
		       for(int i = 0; i < Constants.SIZE; i++){
		    	   int index = i + group * Constants.GROUPSIZE;
		    	   int temp;
		    	   temp = uf.getRoot(index);
		    	   if(temp != -1){
		    		   output.collect(new IntWritable(index), new IntWritable(uf.getRoot(index)));
		    	   }
		    	   temp = uf.getRoot(index+ Constants.GROUPSIZE);
		    	   if(temp != -1){
		        	   if(index + Constants.GROUPSIZE < Constants.SIZE * Constants.SIZE){
		            	   output.collect(new IntWritable(index + Constants.GROUPSIZE), new IntWritable(uf.getRoot(index + Constants.GROUPSIZE)));
		            	   }
		    	   }
		       }
		    }
		}

  static int printUsage() {
    System.out.println("wordcount [-m <maps>] [-r <reduces>] <input> <output>");
    ToolRunner.printGenericCommandUsage(System.out);
    return -1;
  }

  /**
   * The main driver for word count map/reduce program.
   * Invoke this method to submit the map/reduce job.
   * @throws IOException When there is communication problems with the
   *                     job tracker.
   */
  public int run(String[] args) throws Exception {
    JobConf conf = new JobConf(getConf(), Step1.class);
    conf.setJobName("Edges");
    initJobConf(conf);
    conf.setMapperClass(Step1HadoopMapper.class);
    //conf.setCombinerClass(Reduce.class);
    conf.setReducerClass(Step1HadoopReducer.class);
    //conf.setNumReduceTasks();
    List<String> other_args = new ArrayList<String>();
    for(int i=0; i < args.length; ++i) {
      try {
        if ("-m".equals(args[i])) {
          conf.setNumMapTasks(Integer.parseInt(args[++i]));
        } else if ("-r".equals(args[i])) {
          conf.setNumReduceTasks(Integer.parseInt(args[++i]));
        } else if("-c".equals(args[i])){
          Constants.DENSITY = Double.parseDouble(args[++i]);
        } else {
          other_args.add(args[i]);
        }
      } catch (NumberFormatException except) {
        System.out.println("ERROR: Integer expected instead of " + args[i]);
        return printUsage();
      } catch (ArrayIndexOutOfBoundsException except) {
        System.out.println("ERROR: Required parameter missing from " +
                           args[i-1]);
        return printUsage();
      }
    }
    // Make sure there are exactly 2 parameters left.
    if (other_args.size() != 2) {
      System.out.println("ERROR: Wrong number of parameters: " +
                         other_args.size() + " instead of 2.");
      return printUsage();
    }
    FileInputFormat.setInputPaths(conf, other_args.get(0));
    FileOutputFormat.setOutputPath(conf, new Path(other_args.get(1)));

    JobClient.runJob(conf);
    return 0;
  }


  public static void main(String[] args) throws Exception {
    int res = ToolRunner.run(new Configuration(), new Step1(), args);
    System.exit(res);
  }

}
